Cataracts are the clouding of the natural lens of the human eye, which obstructs the provision of enough light for sight or vision. There are three different major types of cataracts, which are cortical cataracts, sclerotic nuclear cataracts, and posterior subcapsular cataracts. Cataracts do not really respect any age, but it occurs more as one gets older; that is, it increases with respect to age. It occurs well in the middle ages of about 40 to 50 years of age, but it gets worsened at age 60 upward.
Why does this happen? It simply happens due to the fact that the proteins of the eye lens decrease or degrade as time goes on. Hypertension and diabetes mellitus, which is also common among the old aged people can also aid the lens proteins degrading process. Some environmental factors such as ultraviolet light, toxins, and radiations accumulate over time, thereby improving cataracts in the eyes. This also alters the chemical processes and gene expressions within the eyes.